You need a slight stop there to collect your thoughts, especially when the next word is achromatopsia. That makes D wrong.
If you use B, " A medical condition that limits her vision" is not a sentence. So B shouldn't be the answer. Fragments are used by very good writers usually in fiction, and this statement is not part of something that is fictional.
A semicolon separates two equal clauses. You can think of it as meaning "and" or even "but" sometimes. You have the same problem with C as you do with B. So C is not correct.
That leaves us with A. That should be your answer.You need a pause of some kind and that pause is proved by the comma. The sentence is not a run on sentence just one in need of a pause in the middle.
Give us more information about the question
The excerpt that tells the White family's uncertainty on the Major's story would be when Mr. White said:
"If the tale about the monkey's paw is not more truthful than those he has been telling us," said Herbert, as the door closed behind their guest, just in time to catch the last train, "we shan't make much out of it." This is because they are not sure what is true about the information that a stranger told them in the train.
Answer:
Fear, the constant companion of the peasant. Hunger, ever at hand to jog his elbow should he relax. Despair, ready to engulf him should he falter. Fear; fear of the dark future; fear of the sharpness of hunger; fear of the blackness of death.
Btw :
Stay safe! ^-^
what do you mean by democracy
