If $$p, q, r, s$$ are in harmonic progression and $$p > s$$, then

A

$$\left(\frac{1}{ps}\right) < \left(\frac{1}{qr}\right)$$

B

$$q + r = p + s$$

C

$$\left(\frac{1}{q}\right) + \left(\frac{1}{p}\right) = \left(\frac{1}{r}\right) + \left(\frac{1}{s}\right)$$

D

None of these