$6$ students will play a total of $5+4+3+2+1=15$ games.  Total score $=15\times2=30$  Last student\textquotesingle s score $=30-7-6-5-4-3=5$ 
In a chinese chess competition, children would be awarded $$2$$ marks for every game won, $$1$$ mark will be awarded for every game that ended in a draw and $$0$$ marks will be awarded for every game that ended in a loss. $6$ students participated in the round robin and $5$ of the students\textquotesingle{} scores are as follows: $$7$$, $$6$$, $$5$$, $$4$$, $$3$$. How many marks did the last place student score? 

[a] $$2$$ 
[b] $$4$$ 
[c] $$5$$ 
[d] $$8$$ 