Institution: Bangladesh Public Service Commission (BPSC) Exam: 18th BCS Question with Answer
Topic: Fill in the Blank, Subject: English Grammar (ইংরেজি গ্রামার)

Best Answer Explained in Below-:

In the sentence "If a ruby is heated it ___ temporarily loses its color," the correct option is C) "will." This is because the sentence implies a conditional situation where the outcome is a result of a specific action—in this case, heating the ruby.

When constructing sentences that describe a cause-and-effect relationship, particularly in the context of conditionals, the first part (the condition) usually presents a situation that can lead to a definite consequence in the second part. In English grammar, this is represented in the first conditional structure, which follows the pattern: "If [present simple], [will + base verb]."

Using "will" denotes a future possibility that is expected to occur as a direct consequence of the condition being fulfilled. Thus, saying "If a ruby is heated, it will temporarily lose its color" signifies that the heating of the ruby causes a predictable reaction—its color loss.

Options A) "has," B) "would," and D) "does" do not convey the same direct causality and future certainty that "will" does in this context. Therefore, "will" is the grammatically and contextually appropriate choice.