Math and commercials

Here's a basic math question:

Question: You have 10 coconuts. Someone gives you 5 more coconuts. What percentage of additional coconuts were you given?

A. 10%
B. 33%
C. 50%
D. 75%

Is this AT&T Commercial correct or did they falsely make a claim?

https://www.youtube.com/watch?v=xDOz6MDSS1Q

 

I could be wrong, but I will say "B."

 

The commercial is correct. These types of calculation are based on the original amount. 5 is half of 10, so you're getting 50% more.

 

15

 

C; 50%
5 coconuts is half of 10 coconuts so having 10 coconuts and receiving an additional 5 coconuts is like receiving half your coconuts.