Among the different philosophical theories, I choose to follow Kant’s theory, which is deontology. It is a theory where the action's adherence to laws or rules is the basis of telling whether an act is considered moral or not. It is also called an “obligation-based” or “duty-based” ethics since rules bind you to your duty. Unlike the theory “utilitarianism” where the good end justifies the means, deontology focuses on what the right thing to do is and not to what is considered good. Deontological theories differ from utilitarian theories in some ways. The most significant difference to take note of is that utilitarianism aims at a goal of greatest happiness (or the best consequence) and justifies any act that achieves that goal. Deontological theories hold that some acts are always wrong, even if the act leads to an admirable outcome. Actions in deontology are always judged independently of their outcome. 

On a personal note, utilitarianism (or consequentialism) is a self-centered theory that only focuses on the achievement of pleasure and happiness. Also, it only benefits a particular group or person, not considering the morality of the means of achieving it. If this is the case, this theory can be taken as "relative" since different people view happiness differently and they have their own definition of what the Good is. However, deontology is a much more ideal philosophical theory to base our morality since it includes specific rules where all people are obliged to follow. By adhering to such rules, we achieve order and that people would also have a clear basis of how to consider a certain act. Although, it is indeed true that actions in deontology and their outcome are independent from each other, I believe that doing the right thing based on a predetermined duty is necessary for people to achieve order and harmony.

 The husband is faced with two possible options given by their doctor: firstly, they can choose to follow the doctor’s recommendation to be able to save the mother by removing the tumor in her body as soon as possible, but it would seriously harm the fetus’s physical form and, in the worst case scenario, it could fatally injure the baby resulting to death or, secondly, the couple can continue the pregnancy and delay the operation until the birth of the child, but the risk would be too great for both the mother and the child since the tumor is growing exponentially. 

Applying the said principle, to be considered as permissible, one’s action must be able to meet the following conditions: First, the action in itself from its very object is good or at least indifferent; second, the good effect and not the evil effect is intended; third, the good effect is not produced by means of the evil effect; fourth, there is a proportionately grave reason for permitting the evil effect. Based on the given conditions, we could say that both the first, considering the intention is to save the mother even with the foreseen death or injury of the baby as a side effect of the said action, and the second option, to risk the chance of saving both the mother and the child, are permissible and in no way they conflict with the said conditions.

 Personally, if I were the husband in that circumstance, I would choose to save the life of my wife by taking the first option. Although both are permissible, I would choose the option where I would be able to save both of them despite the inevitable deformity or harm to the life of my child rather than risking the chance of saving their lives.

 Considering the accountability of the agents in the said situation, they are not considered accountable even if there would be harm foreseen since there is indirect voluntariness which means that the foreseen harm is not intended by the agents despite the knowledge of the consequence. Also, there is also less freedom because the decision is influenced by the risks inherent to the options to be made. Simply saying, the good end outweighs the bad which makes it morally acceptable.