Institution: জাতীয় কবি কাজী নজরুল ইসলাম বিশ্ববিদ্যালয় (JKKNIU) Exam: ক ইউনিট || জাতীয় কবি কাজী নজরুল ইসলাম বিশ্ববিদ্যালয় || 2013
Topic: Sentence (বাক্য), Subject: English Grammar (ইংরেজি গ্রামার)

Best Answer Explained in Below-:

The sentence "I have to go out now" expresses an obligation primarily because it indicates a necessity or requirement for the speaker to leave. The phrase "have to" is crucial in conveying this sense of duty or compulsion. Unlike an order, which implies that someone else is commanding the speaker to do something, or an enquiry, which seeks information, this sentence reflects the speaker's internal sense of obligation.

While a request would typically involve asking someone for permission or assistance, the phrasing here shows no such solicitation. Instead, the speaker is merely stating their need to act—implying that there may be a time constraint or pressing reason behind their decision to go out.

Thus, option D, "obligation," accurately captures the meaning of the sentence, highlighting that the speaker feels compelled or required to undertake this action at this moment, regardless of external pressures or requests. This nuanced understanding of the modal verb "have to" reinforces the idea of obligation as the primary intent of the statement.