Which excerpt from the story “marriage is a private affair” reveals cultural differences that contribute to the dilemma?
a.“[nene] kept her home much better than most of them [the ibo women].”
b.“okeke was trying hard not to think of his two grandsons.”
c.“the boy’s mind is diseased, and only a good herbalist can bring him back . . ”
d.“nnaemeka sat with his father under a cassia tree.”

The correct answer of the given question above would be option C. The excerpt from the story "Marriage is a Private Affair" that reveals cultural differences that contribute to the dilemma is "the boy’s mind is diseased, and only a good herbalist can bring him back . . . .” 

its

theyve

scientists

known,

size

professor

now"

Explanation:

its

Missing apostrophe, it should be "it's"

theyve:

Missing apostrophe, it should be "they've"

scientists:

Missing apostrophe, it should be "scientists' careful"

known,

There should be no comma after this word

size

There should be a comma after this word to correctly separate two independent clauses.

professor

When  the word "professor" is someone's title, like in this case, it requires a capital letter, so it should be "Professor"

now"

Since this is the end of a sentence there´s a missing period mark. It should be: now."