Correct Answer - A
`"Rate of return"=("Face value"xx"Rate of dividend")/("Market value")`
Choice (a) : `"Rate of return"=(40xx4%)/(50)`
`=(16)/(6)%`
Choice (b) : `"Rate of return"=(50xx5%)/(60)`
`=(25)/(6)%`
Choice (c) : `"Rate of return"=(60xx6%)/(70)=(36)/(7)%`.
Choice (d) : `"Rate of return"=(70xx7%)/(80)`
`=(49)/(8)%`.
`therefore` The least attractive scheme is choice (1), since it the yield the least rate of return.