Step 1: Understanding the Question:
For a homologous series of alcohols, the boiling point depends on the molecular weight and surface area.
Step 3: Detailed Explanation:
All given options are primary alcohols capable of hydrogen bonding.
As the carbon chain length increases, van der Waals forces increase, leading to a higher boiling point.
Methanol (\( \text{CH}_3\text{OH} \)) has the smallest carbon chain and lowest molecular weight among the options.
Order of BP: Methanol \( < \) Ethanol \( < \) Propanol \( < \) Butanol.
Step 4: Final Answer:
Methanol has the lowest boiling point.