Although the demand for slaves was great, Angolan and Brazilian merchants only permitted a steady

trickle of slaves into Brazil because
A. there was anxiety over importing tropical diseases that were rife in West Africa.
B. importing too many slaves would reduce their market value.
C. Portuguese Catholics were morally offended by the trade.
D. there was fear of slave revolts.

B makes the most sense -- but check your book.

To understand why Angolan and Brazilian merchants only permitted a steady trickle of slaves into Brazil, we need to analyze the options provided:

A. Anxiety over importing tropical diseases that were rife in West Africa.
B. Importing too many slaves would reduce their market value.
C. Portuguese Catholics were morally offended by the trade.
D. Fear of slave revolts.

A. It is true that tropical diseases were prevalent in West Africa, and there was a legitimate concern about these diseases being imported to Brazil. However, this alone does not explain why a steady trickle of slaves was permitted.

B. This option suggests that importing too many slaves would reduce their market value. It is possible that the merchants wanted to maintain the high market value of slaves by controlling the supply. However, this option alone does not provide a complete explanation.

C. While Portuguese Catholics may have had moral objections to the slave trade, this alone does not address the actions of Angolan and Brazilian merchants. This option does not fully explain their decision to permit a steady trickle of slaves.

D. Fear of slave revolts is a plausible explanation. Slave revolts were a constant concern for slave traders and plantation owners, as they posed a serious threat to their economic and social stability. By limiting the number of slaves that were brought in at any given time, the merchants could potentially reduce the risk of revolt and maintain control over the enslaved population.

Based on this analysis, the most likely answer is D. There was fear of slave revolts. However, it is important to note that historical events can have multiple contributing factors, and it is possible that other factors not listed here also played a role in the merchants' decision-making.