Explanation:

• Posidonia Australis is also known as ribbon weed is a species of seagrass. It was discovered in the shallow waters of the World Heritage Area of Shark Bay in Western Australia. 
• This plant is unique from others as it has twice as many chromosomes as its relatives. This makes it what scientists call a “polyploid”. Polyploids instead of taking half-half genome from both parents, take 100% genome of each of their parents, something not unheard of in plants.

Hence only statement 2nd is correct.