What transition is used to show location a. immediately b. beside c. conversely d. thus

Read the opening lines of sojourner truth's speech "ain't i a woman? " well, children, where there is so much racket there must be something out of kilter. i think that 'twixt the negroes of the south and the women at the north, all talking about rights, the white men will be in a fix pretty soon. but what's all this here talking about? what tone do these lines convey?

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.

What are potential sources of error in marta’s experiment