The following items have a blank space followed by four options. Select the most appropriate option to fill in the blank and mark your response on the Answer Sheet accordingly. The class decided to organise __________.

Step-by-step solution

The word 'picnic' is a singular countable noun and requires an article before it. Since the sentence refers to a general, unspecified event being organized by the class, the indefinite article 'a' is appropriate. Therefore, 'a picnic' is the correct phrase to fill in the blank. Answer: a picnic