How much of the human body is neither made of bones nor skin?

We are given in the first graph that skin is $$\dfrac{1}{10}$$, bones is $$\dfrac{1}{5}$$, muscles is $$\dfrac{3}{10}$$ and the rest is others.

The total sum must be equal to 1.

Skin + Bones + Muscles + others = 1

Others = 1 - Skin - Bones - Muscles

Others $$=\ 1\ -\ \dfrac{1}{10}\ -\ \dfrac{1}{5}\ -\ \dfrac{3}{10}\ =\ \dfrac{10\ -\ 1\ -\ 2\ -\ 3}{10}\ =\ \dfrac{4}{10}$$

Neither bones nor skin = Muscles + others = $$\ \dfrac{3}{10}\ +\ \dfrac{4}{10}\ =\ \dfrac{7}{10}\ =\ \dfrac{7}{10}\ \times\ 100\ =\ 70\%$$

Hence, the correct answer is option D.