past simple or past perfect

the child woke up crying, because he . . . a nightmare.
a) had b) had had
could someone explain to me which answer is correct, please?
thanks in advance

The child experienced the nightmare then woke up. There are a number of actions in the past, one after the other.
Which tense do you think is needed?

i think had had is correct but i am not completly sure could u help me?

“had had” is correct there. Well done.
The pronoun “I” should always be written as a capital letter and there is no such word in English as “u”.

[color=blue]A very strict test marker might only accept “had had” as the correct test answer. But as far as speaking English is concerned, ‘had’ is very acceptable. The meaning is still very clear with only one “had”.

The meaning may be clear, and that was my first thought, but then I decided that use of ‘had’ would be more likely in a slightly adjusted sentence:
The child woke up crying when he had a nightmare.

In the original question here, I would say that the exercise is obviously a formal one designed to test knowledge of the use of the past perfect within a sequence of events.

  I am completely agree with you, Beeesneees, in this respect! I liked your response:-)