Answer:
C.
Step-by-step explanation:
The parent function is y = cos(x).
When we have y = cos(x) + 1, this tells us that the graph has been shifted up by 1.
When we have y = -cos(x), this tells us that the graph has been reflected across the x-axis.
When we have y = 3cos(x), this tells us that the graph has been vertically stretched by a factor of 3.
All together, the answer is C.
Notes:
y = 3cos(x) would be a vertical stretch, while y = cos(3x) would be a horizontal compression.
y = -cos(x) is a reflection across the x-axis, while y = cos(-x) would be a reflection across the y-axis.
