Explanation:

- The sentence discusses what happens to a lemon crop. "A large chunk of lemon crop grown in the country goes ______ to factories." The blank in the sentence requires a word that describes how the crop goes to the factories.

- Option 1: "director" - This is a noun and refers to a person in charge. It doesn't fit here as we need an adverb.

- Option 2: "directing" - This is a verb and doesn't fit the context requiring an adverb.

- Option 3: "directed" - This is the past participle of the verb "direct" but doesn't fit how the action is carried out.

- Option 4: "directly" - This is an adverb and correctly describes how the lemon crop goes to the factories.