Institution: Directorate of Primary Education - DPE Exam: Primary Exam Question Solution 31-05-2019
Topic: Spelling, Subject: English Grammar (ইংরেজি গ্রামার)

Best Answer Explained in Below-:

The correct spelling of the word is "irresistible," which is option C. Understanding its construction can clarify why this is the proper choice. This term is derived from the prefix "in-", meaning "not," and the root word "resist," which comes from the Latin "resistere," meaning "to withstand." The suffix "-ible" denotes the ability or capacity to be acted upon. Therefore, "irresistible" literally translates to "not able to be resisted."

Options A ('iresistible'), B ('iresistable'), and D ('irresistable') are incorrect due to deviations from standard English spelling. Option A incorrectly places an extra 'i' at the beginning, while option B replaces the proper suffix "-ible" with the incorrect "-able." Option D, while closer, still substitutes the correct suffix.

Spelling in English can often be confusing due to varied roots and suffixes from different languages, but familiarizing oneself with common patterns, such as the "-ible" suffix for words derived from Latin, can aid in spelling mastery. Thus, C: "irresistible" is the only accurate representation of this widely used term.