d
Archimedes principal states that weight of body displaced by $liquid=upthrust.$
$60 \times g + V \times 0.6 \times {10^3}\,g = V \times 1000\,g$
$60 + 600\,V = 1000V$
$60 = 400V$
$V = \frac{{60}}{{400}} = \frac{3}{{20}}{m^3}$
Where, $V$ is the volume of wooden log.