Which statement best explains lamarck's theory of acquired characteristics as it relates to the neck length of giraffes?

LAMARCK's THEORY 
                                   Jean Baptiste Lamarck (1744-1829) proposed a theory which was published in "Philosophie Zoologique" (1809).  This theory is simply known as Lamarckism. It has two main postulates:

1. Use and disuse of organs
2. Inheritance of acquired characters.

Example
             He explained his theory by giving the examples:
1. Neck length of Girrafes
2. Webbed toes of water birds, and
3. Wings of penguins

Explanation
               Lamarck explained that water birds use toe for swimming, with the passage of time webbed were developed in their toes. these features were then transferred to their offspring. 

Drawback
                Lamarck theory was based on natural observation. It did not explain the genetic basis of such characteristics.

Ihaven't done that yet, so no idea,but this is not the right place to ask