Compressional or P (for primary)
, Transverse or S (for secondary)
, Love, and Rayleigh. Primary waves push and pull the ground in the direction the wave is traveling. Secondary waves travel in the same direction, but they shake the ground back and forth perpendicular to the direction the wave is traveling. Love waves move back and forth horizontally. Rayleigh waves cause both vertical and horizontal ground motion.
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I am pretty sure it is C but correct me if I'm wrong hope this helps.
I think the common between low-latitude countries would be people's skin color and If you compare the Philippines and its neighboring countries, they have more or less similar physical attributes. Typical Filipinos looked similar with Indonesians.
For Southeast Asia, i would also consider religion is common between the two. Both the Philippines and the other Southeast Asian countries such as Indonesia, Malaysia, and Thailand, they have a large number of Muslim settlers while other tropical countries in South America, these countries have similar Spanish ancestry just like the Philippines.