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.

[EX Q]: Sentence: 'the pigeons are walking around in the park around the benches'. How many words start with the letter 'b' in the sentence.
[EX A]: 1

[EX Q]: Sentence: 'a red and white double decker bus parked in front of a building'. How many words start with the letter 'b' in the sentence.
[EX A]: 2

[EX 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.
[EX A]:
4