Final answer:
The plural form of a singular term ending in -a can be -as or -ae, depending on the word.
Step-by-step explanation:
The plural form of a singular term ending in -a can have multiple variations depending on the word. In general, the most common way to form the plural is by adding -s to the end of the word.
For example, the singular word 'banana' becomes 'bananas' in the plural form. However, some words that end in -a have Latin origins and may take the plural form by adding -ae. For instance, the singular term 'alumna' becomes 'alumnae' in the plural form.
So, the answer to your question is option 3) -as or -ae. It depends on the word you are using.