Hi, yurtik,
If we put these answers under strict scrutiny, we'll find only answer A is both grammatically correct and makes sense. I'll then put down my comments to them for your reference.
A. Both grammatically correct and makes sense
B. Makes sense but not grammatically correct.
(1) We need a conjunction to go between two clauses. The word "probably" looks like a conjunction but it's actually an adverb. If you add "because", which is a rightful conjunction, and make it "probably because", then it'll sound better.
(2) If this is from a test and you want to nail this one, you should go on and change "she was" into "she were". We use the past subjunctive after "as if" in formal English.
C. Makes sense but not grammatically correct
There's a verb agreement error in the second clause. Since the verb in the first clause is in the past tense, we should use "might/may have learned" instead of "may learn" in the second clause.
D. Grammatically correct but makes little sense
E. Grammatically correct but makes little sense