the best answer would be a) having been , because it is in the past and is no longer that way ..also b sounds close but not correct because it is used when talking about a living thing which a virus is not discribes as. well i hope that helps :) good luck! soo the sentence would be : Since having been eradicated, the smallpox virus is found only in laboratories. ~nicamamii~

Yes, A or B. While A sounds better to me.

Believe it or not, this is a tough question to answer. Either a or b are both used, but I myself prefer answer a.

Hi I don't know if the answer will be late, but it will be batter than...! the correct is not the A,or B why? - (having been...)does not exist in English! so,if you want to use the present perfect progressive. It should be ( since -you- have been eradicated ) -active, or ( has been eradicated -the virus- ) -passive. -(being...) is incorrect too ing-verb requires helping verb (be) - ( have been eradicated) is the correct one because the verb-action- (eradicate) has been happened only one time so we use the present perfect ,but if you have been eradicating** the virus many times. you use the present perfect progressive(**). Finally, If my answer is correct(C)! the phrase is going to be a complete sentence,so you need to correct the sentence fragment. ne nada skazat nikakda! ia jolaiu vam yspikhov (homard)

Since being eradicated, smallpox virus is found only in laboratories. A) having been b) Being c) have been (b) is correct because if you just add the noun it will make sense (Since the smallpox virus is eradicated, smallpox virus is found only in laboratories) see what I mean. a) is wrong because of the ed in eradicated it is a past tens. There is no noun in the first part c) is wrong you can not add ing with been