The following sentence has been split into four segments. Identify the segment that contains a grammatical error.
The boy had run away / because he couldn’t stand / his father beat him / for one more day.

Correct option is A

The segment that contains a grammatical error is (a) "his father beat him".
 The verb "beat" is in the simple present tense, while the rest of the sentence is in the past tense. To make the sentence grammatically correct, the verb should also be in the past tense.
 Change "beat" to "beating," the make the sentence grammatically correct and convey the meaning that the boy couldn't tolerate his father's habit of beating him.
 Therefore, the correct sentence would be: "The boy had run away because he couldn't stand his father beating him for one more day."