Which statement is correct? $($Mark one$)$

a$.$

i$)$ unsupervised learning with discrete predictions; ii$)$ supervised learning with continuous predictions; iii$)$ supervised learning with continuous predictions;

b$.$

i$)$ supervised learning with continuous predictions; ii$)$ supervised learning with discrete predictions; iii$)$ unsupervised learning with discrete results;

c$.$

i$)$ supervised learning with discrete predictions; ii$)$ supervised learning with continuous predictions; iii$)$ unsupervised learning with discrete results;

d$.$

All the three scenarios can be solved by unsupervised learning.