Find the part of the sentence that contains an error: The training program was designed (1)/ to make the employees capable to handle (2)/ complex queries efficiently (3)/ in customer support operations. (4)/

Correct — B. The adjective capable is followed by of and a noun or an -ing form: capable of violence, capable of handling.

Part (2) puts a to-infinitive after it: capable to handle. That pattern belongs to able, as in able to handle.

The repair is "to make the employees capable of handling" — option (b).

Why the others are wrong

• (a)
  (1) — The training program was designed is a sound past simple passive. Program is the American spelling of programme, not an error.
• (c)
  (3) — efficiently is an adverb telling how the employees handle the queries, and complex queries is a sound object. Nothing here needs repair.
• (d)
  (4) — in customer support operations is a prepositional phrase saying where the queries are handled. It closes the sentence correctly.

Some adjectives fix the form of the verb that follows them. Capable takes of + -ing: capable of handling, capable of winning.

Its near-synonym able takes a to-infinitive: able to handle. The meanings are close, but the patterns are not.

The same slip turns reputation of being into reputation to be, and prevent someone from doing into prevent someone to do.

Key facts

• Capable takes of + a noun or -ing form: capable of handling complex queries.
• Able takes a to-infinitive: able to handle complex queries.
• Make + object + adjective is a correct pattern: make the employees capable.

Common traps

• Accepting capable to handle because able to handle sounds the same
• Suspecting efficiently in part (3), when it is the adverb the verb handle needs

No directly related past PYQ was found.