marketable stock

(A) any stock which is regularly traded on—

(i) a national securities exchange which is registered with the Securities and Exchange Commission or the national market system established pursuant to section 11A of the Securities and Exchange Act of 1934, or

(ii) any exchange or other market which the Secretary determines has rules adequate to carry out the purposes of this part,

(B) to the extent provided in regulations, stock in any foreign corporation which is comparable to a regulated investment company and which offers for sale or has outstanding any stock of which it is the issuer and which is redeemable at its net asset value, and

(C) to the extent provided in regulations, any option on stock described in subparagraph (A) or (B).