"of" or no "of"?

[vkhu]

"Speech consists not merely of sound but............... that follow various structural patterns"

A) organized sound patterns
B) of organized sound patterns

The key in my book stated that A is the correct answer but I don't get why. Doesn't B fit the bill too? Can someone explain to me why is "of" omitted in this case?

[bhaisahab]

"Speech consists not merely of sound but............... that follow various structural patterns"

A) organized sound patterns
B) of organized sound patterns

The key in my book stated that A is the correct answer but I don't get why. Doesn't B fit the bill too? Can someone explain to me why is "of" omitted in this case?

Both are correct.

[vkhu]

Both are correct.

Wait, what? That was a multiple choice question, How come both of them are correct?

[bhaisahab]

Wait, what? That was a multiple choice question, How come both of them are correct?

It's a bad question.