Loretto Inc. has the following result. For $2019,$ Total assets is $$3,990$ and Total equity is $$2,100.$ What is the debt ratio in $2019?$

a$.$

$52\mathrm{.}63\%$

b$.$

$90\%$

c$.$

$49\mathrm{.}67\%$

d$.$

$47\mathrm{.}36\%$