Question

what strategy did the portuguese use most successfully in building a trading empire in south & southeast asia?
alliances with other european countries
military force against some asian peoples; diplomatic relations with others
invasions deep into asian lands; then divide and conquer
an alliance with china to drive out rival europeans

Explanation:

The Portuguese used a combination of military force against some Asian groups to assert dominance and establish control over key trading - points, while also engaging in diplomatic relations with other Asian powers to facilitate trade. Alliances with other European countries were not the main strategy for building their Asian trading empire. Invasions deep into Asian lands for divide - and - conquer were not as successful or prominent as the military - diplomatic approach. There was no significant alliance with China to drive out rival Europeans.

Answer:

military force against some Asian peoples; diplomatic relations with others