18a. My brother knows more about technology than me.

18b. My brother knows more about technology than I.
my answer is B. please explain answer

Yes, B is correct.

The reason is that in order to compare brother and "I" the two words must be in the same case -- in this instance, they must both be in subject case. The sentence is somewhat truncated. The entire thought would read like this:
"My brother knows more about technology than I do." You wouldn't say "...than me do" right?

http://grammar.ccc.commnet.edu/grammar/cases.htm

oh, thank you!!

The correct answer is actually A, "My brother knows more about technology than me." I will explain why.

In the sentence, "me" is a pronoun that functions as the object of the verb "knows." When comparing two people's knowledge about technology, "me" is the appropriate pronoun to use because it refers to the person who is less knowledgeable (in this case, the speaker).

To understand this, let's break down the sentence:

Subject: My brother
Verb: knows
Object: more about technology
Compared Person: me

In English grammar, we use object pronouns (such as me, you, him, her, etc.) when they are the object of a verb or preposition. In this case, "me" is the object of the verb "knows."

Therefore, the correct sentence is: "My brother knows more about technology than me."

It is a common misconception that the pronoun "I" should be used in comparisons, but that would be incorrect. The use of "I" would be appropriate if the pronoun was being used as the subject of the verb. For example, "I know more about technology than my brother."

I hope this explanation clarifies things for you!