When the pronoun is the main subject
I believe the correct answer is that the <span>speaker may forget ideas or make grammatical mistakes.
Extemporaneous speaking has a lot to do with improvisation - it is a speech where you get a topic you haven't prepared for, and then you have 10-20 minutes to prepare and speak. This way, you cannot memorize everything that you wanted to say, and given that you aren't completely ready to speak, you may make some mistakes.
</span>
3x - y = 5
If you are looking for x, then
3x - y(0) = 5
3x = 5
x = 5/3
If you are looking for y,
3x - y = 5
3(0) - y = 5
-y = 5
-y / -1 , 5 / -1
y = -5
I'd have to say C) but I'm not sure.