Read the paragraph. [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? sentence 1 sentence 2 sentence 3 sentence 4

She took up a scalpel and slit the monkey's abdomen, making a slow and gentle cut, keeping the blade well away from her gloved fingers. the spleen was puffed up and tough, leathery, like a globe of smoked salami. she did not see any bloody lesions inside this monkey. she had expected that the monkey's interior would be a lake of blood, but no, this monkey looked all right, it had not bled into itself. if the animal had died of ebola, this was not a clear case. she opened up the intestine. there was no blood inside it. the gut looked okay. then she examined the stomach. there she found a ring of bleeding spots at the junction between the stomach and the small intestine. this could be a sign of ebola, but it was not a clear sign. it could also be a sign of simian fever, not ebola. therefore, she could not confirm the presence of ebola virus in this animal based on a visual inspection of the internal organs during necropsy.