Why were the Texas colonists “cruelly disappointed"?
The Mexican government had taken away
their land.
The Mexican government did not write a
constitution for them.
The Mexican government had not kept its
promise to protect their rights.

The Texas colonists were cruelly disappointed  because the Mexican government had not kept its promise to protect their rights.

The Texas colonist were the people of Texans which were dominated by the Mexican authority prior to its Independence and integration into the U.S in late 1800s.

Hence, the Texas colonists were cruelly disappointed  because the Mexican government had not kept its promise to protect their rights.

Therefore, the Option C is correct.

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the qing dynasty placed strict limits on foreign merchants' ability to trade in china.

"the sepoy rebellion was the result of many, many influences and stressors on the cultures of india living under british rule. in britain, it's called the sepoy mutiny on the indian mutiny, but in india, it's called the first war of independence.

the main reason is concerned to the british paramountcy , the belief in british   dominance in india political, economic and cultural life had been introduced in india about 1820."

"they were forced to grow crops that benefited the colonizing nations instead of feeding their own people."