It might be said that the first lesson of the poem is to float on one´s back (option A) It seems that a father is teaching his daughter to swim on her back. This can be inferred by the use of certain words such as "Lie back daughter" "spread your arms wide". It also might be understood that the lesson is deep that that, It might suggest a father letting her daughter go, letting her be because she is going to be safe.
The answer is option A (TEXT STRUCTURE)
Text structure<span> is the term used to describe the way information within a written </span>text<span> is organized by the author. Therefore, using the appropriate text structure can help in the organization of supporting evidence.</span>
His last play that he wrote alone. believed to be written 1610-1611 considered on of his greatest works