Practice questions without fighting the page.

<b>Correct answer: D</b> <ul> <li><b>Why</b>: Measles is caused by a virus — specifically the measles virus, an RNA virus in the family Paramyxoviridae (genus Morbillivirus).</li> <li><b>Key concept</b>: Diseases are caused by different pathogens; measles is not bacterial, protozoan, or parasitic in origin.</li> <li><b>Wrong options</b>: A. Bacteria – causes many diseases but not measles. B. Protozoa – causes malaria, amoebiasis, etc. C. Worm – causes helminth infections.</li> </ul> <b>Exam tip:</b> Remember “Measles = viral rash disease.”

<b>Correct option: A</b> – Increased UV radiation <ul> <li><b>Key concept:</b> The ozone layer absorbs most of the sun’s harmful UV-B radiation. A hole reduces this protection, raising surface UV.</li> <li><b>Reason:</b> Ozone depletion → less UV absorption → more UV reaches Earth.</li> <li><b>Formula/numeric logic:</b> UV flux increase is proportional to decrease in ozone column density (approx. ΔUV ∝ 1/ΔO3).</li> <li><b>Exam tip:</b> Remember: ozone hole is linked to UV exposure, not directly to acid rain or greenhouse effects.</li> <li>

A zoonosis is any disease or infection that is naturally transmissible from vertebrate animals to humans.

<b>Correct answer: B. Neil Armstrong</b> <ul> <li>Why correct: Armstrong was the first human to set foot on the Moon during Apollo 11 (1969). He stepped onto the lunar surface first while Buzz Aldrin followed; Michael Collins orbited above in the Command Module.</li> <li>Key concept: lunar landing sequence; order matters in human spaceflight events.</li> <li>Tip: Remember the famous line “one small step for man, one giant leap for mankind.”</li> <li>Why others are incorrect: Aldrin was second on the Moon; Collins did not land on the Moon; Gagarin never reached the Moon (first human in space).</li> </ul>