Answer:
Correct answer is C. the Iberian Peninsula
Step-by-step explanation:
A is not correct as Denmark, marked with number 2, is on the Jutland Peninsula.
B is not correct as Greece, marked with number 5 is on the Balkan Peninsula.
C is correct as Spain and Portugal, which are marked with number 3 are on the Iberian Peninsula.
D is not correct as Italy, marked with number 4 is on the Apennine Peninsula.