The given lines are from Wordsworth's poem Daffodils.
The correct order of the lines is:
\[
\text{For oft, when on my couch I lie,}
\]
\[
\text{In vacant or in pensive mood,}
\]
\[
\text{They flash upon that inward eye,}
\]
\[
\text{Which is the bliss of solitude.}
\]
Now match these with the given letters.
\[
D=\text{For oft, when on my couch I lie}
\]
\[
B=\text{In vacant or in pensive mood}
\]
\[
C=\text{They flash upon the inward eye}
\]
\[
A=\text{Which is the bliss of solitude}
\]
Therefore, the correct sequence is:
\[
D,\ B,\ C,\ A.
\]