Hello

According to the Lamarckian concept :

• According to the theory of inheritance, the characters acquired in a lifetime are transferred to the next generation.
• According to this theory of use and disuse, the organs used most develops most and organs which are left idle reduces in size and function.
• Lamarckism did not put variations under consideration being responsible for the rate of survival of organisms.

So, the correct option is 'Rate of survival of organisms is different due to variations'.

Hope it helps