In which of the following expressions does the expression 'M' > R' does not hold true?

We can check all the options one by one.
from option (a),
M = P > Q > R ? M > R
So, expression M > R holds true for option (a).
From option (b),
M > P ? Q = R ? M > R
So, expression M > R holds true for option (b).
From option (c).
R = P < Q < M ? R < M
So, expression M > R holds true for option (c).
From option (d),
R < Q ? P = M ? R < M
So, expression M > R holds true for option (d)
From option (e),
M = P < Q = R ? M < R
So, expression M > R does not hold true for option (e).