Answer:
The correct answer is "such a".
Step-by-step explanation:
The correct answer is "such a".
The sentence implies that the film was very boring and caused the speaker and others to leave before it finished. The phrase "such a" is used to describe the degree or extent of the boredom, which makes it the appropriate choice here. The phrase "a such" is not grammatically correct, so options (c) and (d) are incorrect. Option (a) "so much" is not incorrect grammatically, but it doesn't fit well in the sentence and doesn't convey the intended meaning.