Suppose a Consumer Has an Income $I = \$ 50$ Which He/she Spends on Pizza and Tacos Per Month

Suppose a consumer has an income $I = \$ 50$ which he/she spends on pizza and tacos per month. The price of pizza is $\$ 10$ and the price of tacos is $\$ 5$ . If the units of pizza consumed per month is on the $x$ -axis and the units of tacos consumed per month is on the $y$ -axis, the slope of the budget line is equal to:

A) $1 / 2$
B) 2
C) $- 2$
D) $2 \mathrm { I }$