[1] tia and jackie are partners in science class. [2] they have a big project to complete and are having trouble agreeing on an idea. [3] jackie would prefer to study geology, but tia is more interested in human biology. [4] ultimately, they decides to study fossilization.
which sentence has a subject-verb agreement error?
a) [1]
b) [2]
c) [3]
d) [4]