The number of moles present in 6 gms of carbon is:

The correct option is 0.5.

To find the number of moles present in a given mass of a substance, we use the standard mole formula:
$$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$$

Let's identify the values given in the problem:
1. Given mass of carbon ($m$) = 6 g
2. Molar mass of carbon ($M$) = 12 g/mol

Now, substitute these values into the formula:
$$\text{Number of moles}=\frac{6\text{g}}{12\text{g/mol}}=0.5\text{moles}$$

Therefore, there is 0.5 mole of carbon present in 6 g of carbon.