Answer:
b) babies can't get enough nourishment to increase their strength
Step-by-step explanation:
The reasons why a newborn's body is not conducive to easy mobility includes;
1. the baby's head is disproportionately larger than its body
2. babies' bodies are mostly fat, not muscle, so they lack the strength to pick their heads up
3. the baby's limbs are relatively short in relation to the rest of the body.
The babies nutrient intake is not a reason, the baby needs to develop muscles with time before he can move. No matter the nutrient intake, growth and development is a process that is gradual and requires time.