Which of the following is thinner than a pen?

Look at the pair of pictures and identify which is thin and which is thick?

Tick the thicker. Circle the thinner.

Tick $\left(\mathrm{✔}\right)$ the thinnest.

Tick the thicker. Circle the thinner.

Colour the thick object in red and thin object in green.

Tick $\left(\mathrm{✔}\right)$ the thinner.

Tick the thicker. Circle the thinner.

Colour the fatter one.

Tick $(\surd )$ the thinner tyre.

Tick $(\surd )$ the thicker book.

Colour the pen that is thicker.

Colour the thick object in red and thin object in green in the following group.

Tick  $(✓)$ the thinnest object.

Colour the thicker candle with red colour and thinner candle with green colour.

Which candle will burn for a long time $?$ Why $?$