The correct option is B b
The option that has an error, is the correct option.
Option B: The
error lies in part (b) as 'seems' is missing the infinitive 'to be' in this sentence. We generally use 'seems' to talk about a subjective mood, that is just a thought. 'Seems to be' refers to something that is really true.
Here, in the sentence, the feeling of worry is real. Hence 'she seems to be worried' is the correct word choice.
So, part b has an error in it.
Hence, option B is the correct option with the error.
The other parts (a) and (c) do not have any error in them. They are grammatically correct and are complete in meaning.
Hence options A and C are not the right answers.
Option D is incorrect because the sentence has an error (b).