Final answer:
The correct answer is option 4: none of these. Words ending with a silent "s" typically remain unchanged in their plural form, meaning no additional "es," "s," or an apostrophe with "s" is added to make them plural.
Step-by-step explanation:
Understanding the Pluralization of Words Ending in Silent "s"
When it comes to words ending in a silent "s," the standard rule for pluralization does not involve adding "es" or an apostrophe and "s". Rather, these words generally follow the typical pattern of simply adding an "s" to form the plural. However, it's important to note that English has many exceptions, and some words may have irregular plural forms. In this case, the plural form of a word ending in a silent "s" is often the same as the singular form, so none of these options provided would be correct.
For example, the word "corps" (which has a silent "s") remains "corps" in both singular and plural. Similarly, "chassis" stays the same in both forms. Unlike typical possessive forms, where 's or s' is added depending on whether the noun is singular or plural, words with a silent "s" at the end do not adopt these changes for their plural forms.