The correct answer is (a) (i), (ii), & (iii).
Explanation: Earthquakes can directly cause tsunamis, landslides, and floods.
Why other options are incorrect:
(b) (ii) & (iv): While landslides can be caused by earthquakes, lightning is not directly related to earthquakes. Earthquakes cause geological changes on the Earth’s surface, whereas lightning is a meteorological phenomenon related to atmospheric electricity.
(c) (ii), (iii) & (iv): This option includes lightning, which is not caused by earthquakes.
(d) (iii) & (iv): This option only includes floods and lightning. Earthquakes can cause floods indirectly through factors like dam damage, but lightning is a separate phenomenon.