Which english word has the same sound as the spanish letter ñ a. panda b. phantom c. banana d. canyon

Canyon is your answer. I hope this help!

The answer you want is Canyon.
Can·yon (the dot is placed on purpose)
 
the ñ has a y sound to it, you can figure this out by going to google translate and just putting in the ñ then click the little speaker. Plus, if you change the word canyon to cañon then click the speaker button in google translate it sounds exactly like if you were to just say "Canyon" 

Hope this helps!

Ps: If you do do google translate MAKE SURE you type you are on the spanish button, as if you are typing in spanish! 

Ithink its b) built underground reservoirs