In this task, you need to count the number of words in a sentence that start with the given letter. Answer with numbers and not words.

[Q]: Sentence: 'a black and white photo of a young man riding a horse'. How many words start with the letter 'a' in the sentence.
[A]: 4


[Q]: Sentence: 'two men are riding horses on a beach'. How many words start with the letter 'r' in the sentence.
[A]: 1


[Q]: Sentence: 'a group of kids on a field playing baseball'. How many words start with the letter 'o' in the sentence.
[A]:
2