The correct option is B Calculation. The term
The sentnce in question here is talking about two different things- first its talking about how al-Khwarizmi's was so influential that his name gave rise to the word algorithm and secondly, its talking about how the word 'algebra', originating from the Arabic word 'al-jabr', also comes from al-Khwarizmi's work. Both of these points are related but not the kind that we can state in one sentence with the use of 'and'. If we do the later then the meaning might not be the same. The use of the full-stop here will bring out the differences in the related ideas of the sentence. So, the answer is option B.