Man ______ how to reach the most distant planets.hasn’t knewdoesn’t knewdidn’t knowdon’t know

Sure, let's analyze the options step by step to find the correct answer for the sentence:

"Man ______ how to reach the most distant planets."

1. hasn’t knew: This option is grammatically incorrect because "hasn't" (has not) should be followed by a past participle, not a simple past tense verb. The correct form would be "hasn't known."

2. doesn’t knew: This option is also grammatically incorrect because "doesn't" (does not) should be followed by the base form of the verb, not the past tense. The correct form would be "doesn't know."

3. didn’t know: This option is grammatically correct and means that in the past, man did not know how to reach the most distant planets. However, it implies that this lack of knowledge was only in the past and may not be true now.

4. don’t know: This option is grammatically incorrect because "don’t" (do not) should be used with plural subjects or with "I" and "you." Since "man" is a singular subject, the correct form would be "doesn't know."

Given these analyses, the correct answer is:

"Man doesn’t know how to reach the most distant planets."