In an attempt to increase tourism, the Polish government has reduced

Official Explanation

Read the Original Sentence Carefully, Looking for Errors:

The error in this sentence comes about as a result of incorrect use of verb tense. "Has reduced" indicates an action that happened in the past and is still in force. The underlined portion of the sentence should thus be in the present tense: are intended to facilitate. Then the sentence ends abruptly. The linking verb "are" requires a complement, and none is given. Since what's meant is that the fares are facilitating travel, an action, the correct wording is they do so.

Scan and Group the Answers Choices:

(A), (D), and (E) are not in the simple present tense, while (B) and (C) are.

Eliminate Wrong Answers Choices:

Since (A), (D), and (E) are not in the simple present tense, they can be eliminated.

(B) correctly begins with the present tense “are,” but it introduces the incorrect "and they have" at the end. They have what? Eliminate

(C) is the only answer choice that fixes both errors, so it's correct.

TAKEAWAY: Pay attention to the clues the sentence gives you as to what verb tense is needed.