Correct (22): It had come …………………………………….. a life-time effort.
Explanation: After the word “had,” the verb must be in past participle form. “Came” is simple past; the correct past participle is “come.”

Correct (23): The road was now down-hill and yet the bus moved as slowly as a sick man walking with the help of another.
Explanation: The earlier lines show the bus already came up the mountain. So the road at this point goes downward, not upward. Therefore, “down-hill” is correct.

Correct (24): … and stood still, like an obstinate bull.
Explanation: “With an obstinate bull” is incorrect because it sounds like the bus is standing together with a bull. We need “like” to make a comparison.

Correct (25): Now, the destination was hardly a mile or two away.
Explanation: The phrase “a mile or away” is incomplete. The correct expression is “a mile or two” to show an approximate short distance.

Correct (26): But the driver was sore and the conductor had no option but to be silent.
Explanation: The whole paragraph is in past tense, so the verb must also be in past tense. “Has” is present tense; the correct past form is “had.”