In the case of two production-inputs. which one of the following is not a property of Isoquants (the production indifference curves)? 

Key points​

Isoquant:

• A firm's equivalent of the consumer indifference curve is called an isoquant.
• An isoquant is a curve that displays all the input configurations that result in the same output level.
• The isoquant curve is also known as an “Equal Product Curve” or “Production Indifference Curve” or Iso-Product Curve.”

Important Points

Properties of isoquant

• Isoquant-product curves slope downward from left to right i.e., it has negative slope.
• Isoquants are convex to the origin
• Two isoquant-product curves never cut each other
• Upper isoquant-product curves represent higher level of output
• Isoquants need not be parallel to each other
• No isoquant can touch either axis
•  Each isoquant is oval-shaped

Hence, 'Concave to the point of origin' is not a property of Isoquant.