Unlike other Mayan cities,
Cancun's commercial power throughout the lowlands seems to be from using its strategic position at the foot of the highlands, which were a source of jade, obsidian, and other valuable commodities.In the original sentence the Mayan cities are compared to “Cancun’s commercial power” which is an incorrect comparison. Mayan cities can be compared to Cancun. Hence A, B and C go out.
(A) Cancun's commercial power throughout the lowlands seems to be from using its strategic position at the foot of
the highlands, which were a source of jade, obsidian, and other valuable commodities
(B) Cancun's commercial power throughout the lowlands seems to have come from using its strategic position at
the foot of the highlands, a source of jade, obsidian, and other valuable commodities
(C) the commercial power of Cancun throughout the lowlands seemed to have come from using its strategic
position at the foot of the highlands, a source of jade, obsidian, and other valuable commodities
(D)
Cancun seemed to be using its strategic position at the foot of the highlands, which was a source of jade,
obsidian, and other valuable commodities, in becoming a commercial power throughout the lowlands. Idiom: (Using X in becoming Y), this is idiomatically incorrect.
USE has 2 idiomatically correct forms:
1. USES X to Y.(Used in option E).
2. USES X as Y.
Which modifies “foot of highlands” or “highlands” this is ambiguous.
The sentence makes it feel like it was the thing of past, while in the original sentence the author intends to talk about it in the present.
(E)
Cancun seems to have used its strategic position at the foot of the highlands, a source of jade, obsidian, and
other valuable commodities, to become a commercial power throughout the lowlands. Right Idiom: (USED X to become Y)
Right Tense Mood.
Ambiguity about which is resolved here. Where “a source of jade, obsidian, and other valuable commodities,” a noun phrase modifies the noun “foot of the highlands”