Well, son, I’ll tell you:
Life for me ain’t been no crystal stair
It’s had tacks in it,
And splinters
And boards torn up,
And places with no carpet on the floor –
Bare.
But all the time
I’se been a-climbin’ on,
And reachin’ landin’s,
And turnin’ corners,
And sometimes goin’ in the dark,
Where there ain’t been no light.
So boy, don’t you turn back.
Don’t you set down on the steps
‘Cause you finds it’s kinder hard,
Don’t you fall now –
For I’se still goin’, honey,
I’se still climbin’,
And life for me ain’t no crystal stair.

Which colloquial form of English is used in the poem?

The correct option is African-American English.

This poem, titled "Mother to Son" by Langston Hughes, utilizes African-American Vernacular English (AAVE), also known as African-American English (AAE) or Ebonics, to capture the authentic voice of the speaker (the mother) and convey her message of resilience and endurance.

We can identify this colloquial form of English through several distinct linguistic features present in the text:
1. Double Negatives (Negative Concord): The phrase "ain't been no crystal stair" and "ain't been no light" use double negatives (e.g., ain't + no) for emphasis, which is a classic feature of African-American English.
2. Non-standard Verb Forms and Contractions: The use of "ain't" as a general negative auxiliary verb (standing in for "has not" or "is not") is highly prominent.
3. Pronunciation/Spelling representation: Words like "a-climbin'", "reachin'", "turnin'", and "goin'" drop the final "g" in "-ing", reflecting colloquial spoken rhythms. The spelling "‘Cause" for "because" and "kinder" for "kind of" also denote spoken vernacular pronunciation.
4. Habitual Aspect / Aspectual Marker "I'se": The contraction "I'se" (representing "I has", "I is", or "I have") in "I’se been a-climbin’ on" is another dialectal marker used to indicate ongoing or habitual action.
5. Informal Pronouns and Terms of Endearment: The terms "son", "boy", and "honey" are typical colloquial addresses, and "don’t you set down" uses "set" in place of "sit", which is common in regional and vernacular forms of American English, particularly AAVE.

Therefore, these grammatical patterns, vocabulary choices, and phonetic spellings collectively demonstrate the use of African-American English.