From a trade exchange of artists from ancient Crete, people in other countries learned a method that artists are able to use painting pigment into wet plaster for extending the durability of murals, now known as fresco.
A. that artists are able to use painting pigment into wet plaster for extending the durability of murals
<incorrect> usage of able and use does not convey meaning precisely. However, the modifier "now known as" correctly points to the method.
B. that artists could use to extend the durability of murals by painting pigment into wet plaster
<correct> Conveys the correct meaning
C. for artists who could use painting pigment into wet plaster to extend the durability of murals
<incorrect> Usage of "for artists" does not convey the correct meaning. The intended meaning is to describe the method.
D. for the durability of murals to be extended by artists painting pigment into wet plaster
<incorrect> method is learned for the durability conveys incorrect meaning.
E. of artists able to extend with painting pigment into wet plaster the durability of murals
<incorrect> verb usage of "able" is incorrect with no proper noun reference for "able". Conveys a non-sensical meaning
EMPOWERgmatVerbalIs the comma after murals correct?