Frog’s heart when taken out of the body continues to beat for some time. 
Select the best option from the following statements. 
(a) Frog is a poikilotherm. 
(b) Frog does not have any coronary circulation. 
(c) Heart is "myogenic" in nature 
(d) Heart is autoexcitable

1. Only (d)

2. (a) and (b)

3. (c) and (d)

4. Only (c)