Step 1: Picture methane losing hydrogens one at a time.
When methane reacts with chlorine under sunlight, the reaction does not stop after replacing just one hydrogen, it keeps going in stages, swapping one hydrogen for chlorine at each step.
Step 2: Track the stages. \[ \text{CH}_4 \to \text{CH}_3\text{Cl} \to \text{CH}_2\text{Cl}_2 \to \text{CHCl}_3 \to \text{CCl}_4 \] Each arrow represents one more hydrogen atom being replaced by a chlorine atom, releasing $\text{HCl}$ at every step.
Step 3: Identify the third stage product.
After three hydrogens have been swapped out, we are left with $\text{CHCl}_3$, which is commonly known as chloroform or trichloromethane.
Step 4: Match to the options.
Since this compound genuinely appears along the chlorination pathway of methane, it is one of the valid products of the reaction, unlike DDT, freon, or alcohol which are unrelated substances. \[ \boxed{\text{Chloroform}} \]