Electrochemistry

The $${\left( {{{\partial E} \over {\partial T}}} \right)_P}$$ of different types of half cells are as follows: .tg {border-collapse:collapse;border-spacing:0;} .tg td{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px; overflow:hidden;padding:10px 5px;word-break:normal;} .tg th{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px; font-weight:normal;overflow:hidden;padding:10px 5px;word-break:normal;} .tg .tg-baqh{text-align:center;vertical-align:top} .tg .tg-c3ow{border-color:inherit;text-align:center;vertical-align:top} A B C D $$1 \times {10^{ - 4}}$$ $$2 \times {10^{ - 4}}$$ $$0.1 \times {10^{ - 4}}$$ $$0.2 \times {10^{ - 4}}$$ (Where E is the electromotive force) Which of the above half cells would be preferred to be used as reference electrode?