Find the Slope of the Line (If It Exists) and the Y-Intercept

Multiple Choice

Find the slope of the line (if it exists) and the y-intercept (if it exists) .
- $$3 y = 21$$

A) Slope $0 ; y$ -intercept $( 7,0 )$
B) Slope undefined; $\mathrm { y }$ -intercept $( 7,0 )$
C) Slope undefined; $\mathrm { y }$ -intercept $( 0,7 )$
D) Slope $0 ; y$ -intercept $( 0,7 )$