Part A:
The most likely author's intent by mentioning that Samuel almost drowned at the end of the first paragraph is:
B: To warrant the description of the river.
This mention signifies the river's dangers and establishes its significance in Samuel's life, likely leading into further descriptions of his experiences associated with it.
Part B:
The evidence from the text that best supports the answer in Part A is:
B: He thought life on the river was like a journey through a jungle.
This statement underscores the adventurous and perilous nature of life on the river, which connects to the idea that the river plays a crucial role in Samuel's experiences, even highlighting its dangers, such as nearly drowning.