Explanation:

It can be used directly as a fuel for internal combustion.

True. Hydrogen can be used as a direct fuel in internal combustion engines, similar to gasoline or diesel. Although engines might need certain modifications, hydrogen combustion produces water as the primary byproduct.

It can be blended with natural gas and used as fuel for heat or power generation.

True. Hydrogen can be blended with natural gas to produce what is often called "hydrogen-enriched natural gas" or "hythane." This blend can be used in power plants or domestic heating systems. By blending hydrogen with natural gas, the combustion process can be made cleaner, as the proportion of carbon dioxide emissions is reduced.

It can be used in the hydrogen fuel cell to run vehicles.

True. Fuel cells convert hydrogen into electricity through an electrochemical process, and the electricity is then used to power electric motors in vehicles. Hydrogen fuel cell vehicles (FCVs) are already available in the market and are considered zero-emission vehicles since their only byproduct is water.

Given the evaluations, all three statements are correct.