Answer:
Violating 'Ceteris Paribus' {Other factors constant} assumption, as both food & space are varied (simultaneously)
Step-by-step explanation:
Weight Growth is the dependent (effected) variable in this case. And, independent (causal) variables are food amount are living space respectively.
However particular independent factor's (food or living space) impact on dependent variable ie weight growth : can be determined only by - examining individual variable (food or living space) impact on weight growth. So, either of the two variables should be varied, & not both should be varied simultaneously.
This would imply depiction of each factor's clearer individual impact on the dependent factor.